Watlow 97 series, Руководство пользователя

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Wa t l o w S e r i e s 9 7 F e a t u r e s
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5 . 1 1
Communications
Overview
A Series 97 controller can also be programmed and monitored by connecting it to a personal
computer or programmable logic controller (PLC) via serial communications. To use this
communications option, a Series 97 must be equipped with an output 4 communications
board for EIA/TIA-485 (97_ _ - _ _ _U - _ _ _ _), which allows as many as 32 controllers on a
4,000-foot-long network, or EIA/TIA-232 (97_ _ - _ _ _R - _ _ _ _), which allows a single con-
troller to be connected to a computer.
The Series 97 uses an 8-N-1 data format (eight data bits, no parity, one stop bit and one
start bit).
To view or change controller settings with a personal computer, you need to run software
that uses the Modbus RTU protocol to read or write to registers in the controller. These reg-
isters contain the parameter values that determine how the controller will function and the
values that reflect the current input and output values of the system. The parameters chap-
ter lists the modbus address and range for each parameter. Refer to setup parameter table
for setup order.
Communications parameters appear in the Output 4 Menu (Setup Page). Match the Baud
Rate
[baud] to that of the computer and select an Address [Addr] for each Series 97.
The wiring chapter shows how to wire a Series 97 controller for EIA/TIA-485 or EIA/TIA-
232 communications.
The Appendix provides technical information about programming for Modbus RTU.